1 /* $NetBSD: vfs_init.c,v 1.28 2005/06/05 23:47:48 thorpej Exp $ */ 2 3 /*- 4 * Copyright (c) 1998, 2000 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 9 * NASA Ames Research Center. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the NetBSD 22 * Foundation, Inc. and its contributors. 23 * 4. Neither the name of The NetBSD Foundation nor the names of its 24 * contributors may be used to endorse or promote products derived 25 * from this software without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 37 * POSSIBILITY OF SUCH DAMAGE. 38 */ 39 40 /* 41 * Copyright (c) 1989, 1993 42 * The Regents of the University of California. All rights reserved. 43 * 44 * This code is derived from software contributed 45 * to Berkeley by John Heidemann of the UCLA Ficus project. 46 * 47 * Source: * @(#)i405_init.c 2.10 92/04/27 UCLA Ficus project 48 * 49 * Redistribution and use in source and binary forms, with or without 50 * modification, are permitted provided that the following conditions 51 * are met: 52 * 1. Redistributions of source code must retain the above copyright 53 * notice, this list of conditions and the following disclaimer. 54 * 2. Redistributions in binary form must reproduce the above copyright 55 * notice, this list of conditions and the following disclaimer in the 56 * documentation and/or other materials provided with the distribution. 57 * 3. Neither the name of the University nor the names of its contributors 58 * may be used to endorse or promote products derived from this software 59 * without specific prior written permission. 60 * 61 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 62 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 63 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 64 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 65 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 66 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 67 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 68 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 69 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 70 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 71 * SUCH DAMAGE. 72 * 73 * @(#)vfs_init.c 8.5 (Berkeley) 5/11/95 74 */ 75 76 #include <sys/cdefs.h> 77 __KERNEL_RCSID(0, "$NetBSD: vfs_init.c,v 1.28 2005/06/05 23:47:48 thorpej Exp $"); 78 79 #include <sys/param.h> 80 #include <sys/mount.h> 81 #include <sys/time.h> 82 #include <sys/vnode.h> 83 #include <sys/stat.h> 84 #include <sys/namei.h> 85 #include <sys/ucred.h> 86 #include <sys/buf.h> 87 #include <sys/errno.h> 88 #include <sys/malloc.h> 89 #include <sys/systm.h> 90 91 /* 92 * Sigh, such primitive tools are these... 93 */ 94 #if 0 95 #define DODEBUG(A) A 96 #else 97 #define DODEBUG(A) 98 #endif 99 100 /* 101 * The global list of vnode operations. 102 */ 103 extern const struct vnodeop_desc * const vfs_op_descs[]; 104 105 /* 106 * These vnodeopv_descs are listed here because they are not 107 * associated with any particular file system, and thus cannot 108 * be initialized by vfs_attach(). 109 */ 110 extern const struct vnodeopv_desc dead_vnodeop_opv_desc; 111 extern const struct vnodeopv_desc fifo_vnodeop_opv_desc; 112 extern const struct vnodeopv_desc spec_vnodeop_opv_desc; 113 extern const struct vnodeopv_desc sync_vnodeop_opv_desc; 114 115 const struct vnodeopv_desc * const vfs_special_vnodeopv_descs[] = { 116 &dead_vnodeop_opv_desc, 117 &fifo_vnodeop_opv_desc, 118 &spec_vnodeop_opv_desc, 119 &sync_vnodeop_opv_desc, 120 NULL, 121 }; 122 123 /* 124 * This code doesn't work if the defn is **vnodop_defns with cc. 125 * The problem is because of the compiler sometimes putting in an 126 * extra level of indirection for arrays. It's an interesting 127 * "feature" of C. 128 */ 129 typedef int (*PFI)(void *); 130 131 /* 132 * A miscellaneous routine. 133 * A generic "default" routine that just returns an error. 134 */ 135 /*ARGSUSED*/ 136 int 137 vn_default_error(void *v) 138 { 139 140 return (EOPNOTSUPP); 141 } 142 143 /* 144 * vfs_init.c 145 * 146 * Allocate and fill in operations vectors. 147 * 148 * An undocumented feature of this approach to defining operations is that 149 * there can be multiple entries in vfs_opv_descs for the same operations 150 * vector. This allows third parties to extend the set of operations 151 * supported by another layer in a binary compatibile way. For example, 152 * assume that NFS needed to be modified to support Ficus. NFS has an entry 153 * (probably nfs_vnopdeop_decls) declaring all the operations NFS supports by 154 * default. Ficus could add another entry (ficus_nfs_vnodeop_decl_entensions) 155 * listing those new operations Ficus adds to NFS, all without modifying the 156 * NFS code. (Of couse, the OTW NFS protocol still needs to be munged, but 157 * that is a(whole)nother story.) This is a feature. 158 */ 159 160 /* 161 * Init the vector, if it needs it. 162 * Also handle backwards compatibility. 163 */ 164 static void 165 vfs_opv_init_explicit(const struct vnodeopv_desc *vfs_opv_desc) 166 { 167 int (**opv_desc_vector)(void *); 168 const struct vnodeopv_entry_desc *opve_descp; 169 170 opv_desc_vector = *(vfs_opv_desc->opv_desc_vector_p); 171 172 for (opve_descp = vfs_opv_desc->opv_desc_ops; 173 opve_descp->opve_op; 174 opve_descp++) { 175 /* 176 * Sanity check: is this operation listed 177 * in the list of operations? We check this 178 * by seeing if its offset is zero. Since 179 * the default routine should always be listed 180 * first, it should be the only one with a zero 181 * offset. Any other operation with a zero 182 * offset is probably not listed in 183 * vfs_op_descs, and so is probably an error. 184 * 185 * A panic here means the layer programmer 186 * has committed the all-too common bug 187 * of adding a new operation to the layer's 188 * list of vnode operations but 189 * not adding the operation to the system-wide 190 * list of supported operations. 191 */ 192 if (opve_descp->opve_op->vdesc_offset == 0 && 193 opve_descp->opve_op->vdesc_offset != VOFFSET(vop_default)) { 194 printf("operation %s not listed in %s.\n", 195 opve_descp->opve_op->vdesc_name, "vfs_op_descs"); 196 panic ("vfs_opv_init: bad operation"); 197 } 198 199 /* 200 * Fill in this entry. 201 */ 202 opv_desc_vector[opve_descp->opve_op->vdesc_offset] = 203 opve_descp->opve_impl; 204 } 205 } 206 207 static void 208 vfs_opv_init_default(const struct vnodeopv_desc *vfs_opv_desc) 209 { 210 int j; 211 int (**opv_desc_vector)(void *); 212 213 opv_desc_vector = *(vfs_opv_desc->opv_desc_vector_p); 214 215 /* 216 * Force every operations vector to have a default routine. 217 */ 218 if (opv_desc_vector[VOFFSET(vop_default)] == NULL) 219 panic("vfs_opv_init: operation vector without default routine."); 220 221 for (j = 0; j < VNODE_OPS_COUNT; j++) 222 if (opv_desc_vector[j] == NULL) 223 opv_desc_vector[j] = 224 opv_desc_vector[VOFFSET(vop_default)]; 225 } 226 227 void 228 vfs_opv_init(const struct vnodeopv_desc * const *vopvdpp) 229 { 230 int (**opv_desc_vector)(void *); 231 int i; 232 233 /* 234 * Allocate the vectors. 235 */ 236 for (i = 0; vopvdpp[i] != NULL; i++) { 237 /* XXX - shouldn't be M_VNODE */ 238 opv_desc_vector = 239 malloc(VNODE_OPS_COUNT * sizeof(PFI), M_VNODE, M_WAITOK); 240 memset(opv_desc_vector, 0, VNODE_OPS_COUNT * sizeof(PFI)); 241 *(vopvdpp[i]->opv_desc_vector_p) = opv_desc_vector; 242 DODEBUG(printf("vector at %p allocated\n", 243 opv_desc_vector_p)); 244 } 245 246 /* 247 * ...and fill them in. 248 */ 249 for (i = 0; vopvdpp[i] != NULL; i++) 250 vfs_opv_init_explicit(vopvdpp[i]); 251 252 /* 253 * Finally, go back and replace unfilled routines 254 * with their default. 255 */ 256 for (i = 0; vopvdpp[i] != NULL; i++) 257 vfs_opv_init_default(vopvdpp[i]); 258 } 259 260 void 261 vfs_opv_free(const struct vnodeopv_desc * const *vopvdpp) 262 { 263 int i; 264 265 /* 266 * Free the vectors allocated in vfs_opv_init(). 267 */ 268 for (i = 0; vopvdpp[i] != NULL; i++) { 269 /* XXX - shouldn't be M_VNODE */ 270 free(*(vopvdpp[i]->opv_desc_vector_p), M_VNODE); 271 *(vopvdpp[i]->opv_desc_vector_p) = NULL; 272 } 273 } 274 275 #ifdef DEBUG 276 static void 277 vfs_op_check(void) 278 { 279 int i; 280 281 DODEBUG(printf("Vnode_interface_init.\n")); 282 283 /* 284 * Check offset of each op. 285 */ 286 for (i = 0; vfs_op_descs[i]; i++) { 287 if (vfs_op_descs[i]->vdesc_offset != i) 288 panic("vfs_op_check: vfs_op_desc[] offset mismatch"); 289 } 290 291 if (i != VNODE_OPS_COUNT) { 292 panic("vfs_op_check: vnode ops count mismatch (%d != %d)", 293 i, VNODE_OPS_COUNT); 294 } 295 296 DODEBUG(printf ("vfs_opv_numops=%d\n", VNODE_OPS_COUNT)); 297 } 298 #endif /* DEBUG */ 299 300 /* 301 * Routines having to do with the management of the vnode table. 302 */ 303 struct vattr va_null; 304 305 /* 306 * Initialize the vnode structures and initialize each file system type. 307 */ 308 void 309 vfsinit(void) 310 { 311 __link_set_decl(vfsops, struct vfsops); 312 struct vfsops * const *vfsp; 313 314 /* 315 * Initialize the namei pathname buffer pool and cache. 316 */ 317 pool_init(&pnbuf_pool, MAXPATHLEN, 0, 0, 0, "pnbufpl", 318 &pool_allocator_nointr); 319 pool_cache_init(&pnbuf_cache, &pnbuf_pool, NULL, NULL, NULL); 320 321 /* 322 * Initialize the vnode table 323 */ 324 vntblinit(); 325 326 /* 327 * Initialize the vnode name cache 328 */ 329 nchinit(); 330 331 #ifdef DEBUG 332 /* 333 * Check the list of vnode operations. 334 */ 335 vfs_op_check(); 336 #endif 337 338 /* 339 * Initialize the special vnode operations. 340 */ 341 vfs_opv_init(vfs_special_vnodeopv_descs); 342 343 /* 344 * Establish each file system which was statically 345 * included in the kernel. 346 */ 347 vattr_null(&va_null); 348 __link_set_foreach(vfsp, vfsops) { 349 if (vfs_attach(*vfsp)) { 350 printf("multiple `%s' file systems", 351 (*vfsp)->vfs_name); 352 panic("vfsinit"); 353 } 354 } 355 } 356